Mold Glossary

Absidia
A zygomycete fungus. Reported to be allergenic. May cause mucorosis in immune
compromised individuals. The sites of infection are the lung, nasal sinus,
brain, eye and skin. Infection may have multiple sites.

Acremonium(Cephalosporium)
Reported to be allergenic. Can produce a trichothecene toxin that is toxic
if ingested. It was the primary fungus identified in at least two houses
where the occupant complaints were nausea, vomiting and diarrhea. Asexual
state of Emericellopsis sp., Chaetomium sp., and Nectripsis sp.
It can produce mycetomas, infections of the cornea and nails.

Alternaria
Aw - 0.89. Conidia dimensions: 18-83 x 7-18 microns. This is one of the
main fungal causes of allergy, being a common type I (ex.: hay fever, asthma) & type
III (ex.: hypersensitivity pneumonitis) allergen. The large spore size
suggests that this fungus will settle in the nose, mouth, and upper respiratory
tract, causing nasal septum infections. Alternaria is a common cause
of extrinsic asthma, with acute symptoms including edema and bronchiospasms;
chronic cases may develop pulmonary emphysema. “Baker’s asthma” is commonly
associated with inhalation of Alternaria conidia present in flour. Other
diseases caused by this mold include: “farmer’s lung”, “woodworker's lung”, “apple
store hypersensitivity”, mycotic keratitis (fungal infection of the cornea),
nasal lesions, subcutaneous lesions, skin infections, nail infections, and
osteomyelitis (inflammation of the bone). [It should be noted that most
of the reported infections affected persons with underlying disease or those
taking immunosuppressive drugs.]

Toxic metabolites (that may
cause disease in humans) produced by these microbes include AME (alternariol
monomethylether), tenuazonic acid, and
altertoxins (which are mutagenic). Several species are pathogenic
to plants, and some are processed for use in the biocontrol
of weeds and other plants. A. alternata produces alternariol, an antifungal
metabolite.

Alternaria is commonly
found indoors in dust, carpeting, textiles, on foodstuffs, and horizontal
surfaces (such as window frames). It
has also been isolated from substrates such as sewage, leather, stone monuments,
optical instruments, cosmetics, computer disks, and even jet fuel. Outdoors,
it may be found on dead organic debris, seeds, plants (and
can contribute to the spoilage of agricultural products), in soil, and
air--one of the
reasons that it is a widespread genus. Alternaria conidia
are easily carried by the wind, with peak air concentrations
occurring in the summer and early fall. Colonies grow fast, are suede-like
to floccose, and black to olivaceous-black or grayish in color.

amerosporeA spherical or oval single-celled fungal spore that is
practically unidentifiable by itself. Generawith this
type of sporeinclude, but are not limited to, Aspergillus, Penicillium,
and Trichoderma.For example, Penicillium is easily identifiable when sampling using
culturing techniques. However, when sampling with non-culturing techniques,
such as spore traps or tape-lifts, the free spores with no remnants of the
fungal structure are indistinguishable from Aspergillus and various
other genera that also produce small round and oval spores with little or no
pigmentation. Due to this fact, Penicillium will often be categorized on laboratory
reports in an "amerospore" and/or "Aspergillus/Penicillium" group.

ArthriniumWidespread saprophyte found on decomposing plant material,
particularly grasses, and on soil. It is a white, fuzzy mold.
It should be considered to be an allergen. This fungus has
also been documented in various subcutaneous infections. No
diseases related to toxic effects have been recorded to date.

ascosporeA spore borne in a special cell called an ascus. Spores
of this type are reported to be allergenic.
All ascomycetes, members of a group of fungi called Ascomycotina,
have this type of spore. The minute black dots on rotting wood
and leaves or the little
cups on lichens are examples of ascomycetes; another is the "truffle" mushroom.

Aspergillus caesiellusThis species is only occasionally pathogenic.

Aspergillus candidusAw 0.75. Conidia dimensions: 2.5-4 microns. Found in
warm soils, grain and in the secondary decay of vegetation.
Associated with respiratory complaints in a recent house investigation.
Can produce the toxin petulin that may be associated with disease
in humans and other animals.

Aspergillus carneusThis species is only occasionally pathogenic.

Aspergillus clavatusConidia dimensions: 3-4.5 x 2.5-4.5 microns. Found
in soils and animal manure.
Can produce the toxin petulin that may be associated with disease in humans
and other animals. This species is only occasionally pathogenic.

Aspergillus deflectusThis species is only occasionally pathogenic.

Aspergillus flavusAw 0.78. Conidia dimensions: 3-6 microns or 3-5 microns.
It grows on moldy corn and peanuts. It can be found in warm
soil, foods and dairy products. Some strains are capable of
producing a group of mycotoxins- in the aflatoxin group. Aflatoxins
are known animal carcinogens. There is limited evidence to
suggest that this toxin is a human carcinogen. The toxin is
poisonous to humans by ingestion. It may also result in occupational
disease via inhalation. Experiments have indicated that it
is teratogenic and mutagenic. It is toxic to the liver. It
is reported to be allergenic. Its presence is associated with
reports of asthma. It can be found in water-damaged carpets.
The production of the fungal toxin is dependent on the growth
conditions and on the substrate used as a food source. This
fungus is associated with aspergillosis of the lungs and/or
disseminated aspergillosis. This fungus is occasionally identified
as the cause of corneal, otomycotic and nasoorbital infections.

Aspergillus fumigatusAw 0.82; Optimum> 0.97. Conidia dimensions: 2-3.5
microns. Considered a human pathogen, this organism causes
both allergic aspergillosis and invasive aspergillosis (invasive
aspergillosis usually affects individuals who are immune compromised).
It is commonly found outdoors on cereal grains, in cool to
warm soils, and in compost piles (even with temperatures exceeding
40 degrees C).

Aspergillus glaucusConidia dimensions: 5-6.5 microns. Common outdoor fungus
in the winter. It is reported to be allergenic. This species
is only occasionally pathogenic. It can grow on leather. This
fungus can grow at low moisture levels on grains, sugary food
products, meat and wool. The ascomycetous state is Eurotium sp.

Aspergillus nidulansAw 0.78. Conidia dimensions: 2-4 microns. Found in
mild to warm soils and on slowly decaying plants. Can produce
the mycotoxin sterigmatocystin. This toxin has been shown to
produce liver and kidney damage in lab animals. This fungus
is associated with aspergillosis of the lungs and/or disseminated
aspergillosis. This species is only occasionally pathogenic.

Aspergillus nigerAw 0.77; Optimum> 0.97. Conidia dimensions: 3.5
- 5 microns or 4 to 5 microns. Less common cause of aspergillosis.
It has a musty odor. It is commonly found in the environment
on textiles, in soils, grains, fruits and vegetables. It has
been reported to cause skin and pulmonary infections. It is
a common cause of fungal related ear infections, including
otomycosis.

Aspergillus ochraceusAw 0.77. Conidia dimensions: 2.5 - 3 microns. Found
in grains, soil and salted food products. It is not usually
associated with decaying vegetation. Can produce a kidney toxin
ochratoxin A that may produce ochratoxicosis in humans. This
is also known as Balkan nephropathy. The toxin is produced
at optimum growth conditions at 25 degrees C and high moisture
conditions. The ochratoxin may also be produced by other Aspergillus sp. and Penicillium sp. Other
toxins that can be produced by this fungus include penicillic
acid, xanthomegnin and viomellein. These are all reported to
be kidney and liver toxins.

Aspergillus oryzaeThis species is only occasionally pathogenic.

Aspergillus parasiticusSome strains are capable of producing a group of mycotoxins-
in the aflatoxin group. Aflatoxins are known animal carcinogens.
There is limited evidence to suggest that this toxin is a human
carcinogen. The toxin is a poisonous to humans by ingestion.
Experiments have indicated that it is teratogenic and mutagenic.
It is toxic to the liver. The production of the fungal toxin
is dependent on the growth conditions and on the substrate
used as a food source.

Aspergillus/Penicillium-Like
This category is included on laboratory analysis reports for air samples containing
certain free spores without other identifying structures.The free
spores of Aspergillus and Penicillium (and other genera
with small, round or ovoid, and colorless spores) are essentially indistinguishable,
using standard microscopic examination methods.

If required, cultured specimens can provide additional characteristics
that will enable technicians to determine what genus is represented. If
sporulating structures are present, Aspergillus is readily identifiable
on tape samples. [Discovery of the Aspergillus species requires
the culture of the fungus under different conditions of media, humidity,
and temperature. Identifying Penicillium species is difficult,
but, in some cases, possible.]

These two allergenic molds are among those most often found in contaminated
buildings. Aspergillus is represented by numerous species, many
of which produce toxic substances. It may be associated with symptoms such
as sinusitis, allergic bronchiopulmonary aspergillosis, and other allergic
symptoms. As if not to be outdone, Penicillium too is found in increased
numbers in interiors. Some of its many species produce toxic substances
that can cause allergic reactions, mucous membrane irritation, headaches,
vomiting, and diarrhea.

Aspergillus penicilloidesConidia dimensions: 3-3.5 x 4-5 microns. Can grow in
areas with low water activity. It is found in house dust and
food.

Aspergillus restrictusThis species is only occasionally pathogenic.

AspergillusAw 0.75 - 0.82. Reported to be allergenic. Members of this
genus are reported to cause ear infections. Many species produce
mycotoxins that may be associated with disease in humans and
other animals. Toxin production is dependent on the species
or a strain within a species and on the food source for the
fungus. Some of these toxins have been found to be carcinogenic
in animal species. Several toxins are considered potential
human carcinogens. Common cause of extrinsic asthma (immediate-type
hypersensitivity: type I). Acute symptoms include edema and
bronchiospasms; chronic cases may develop pulmonary emphysema;
may also be associated with sinusitis, allergic bronchiopulmonary
aspergillosis, and other allergic symptoms.

Aspergillus sydowiThis species is only occasionally pathogenic.

Aspergillus terreusAw 0.78. Conidia dimensions: 1.8-2.4 microns or 2 -
2.5 microns. Aleurospores 6 - 7 microns in diameter are also
produced. Found in warmer soil and in grains, straw, cotton
and decomposing vegetation. Can produce the toxin patulin and
citrinin that may be associated with disease in humans and
other animals. This fungus is associated with aspergillosis
of the lungs and or disseminated aspergillosis. Found as an
isolate from otomycosis - ear infection, and onychomycosis
- infection of finger or toenails.

Aspergillus ustusThis species is only occasionally pathogenic.

Aspergillus versicolorAw 0.78. Conidia dimensions: 2-3.5 microns. Mostly
in temperate zones, it is commonly found in air, house dust,
foods (including dairy products), soil, hay, and cotton. It
sometimes produces the mycotoxin "sterigmatocystin",
which can cause diarrhea and upset stomach, and is a possible
carcinogen, affecting the liver and kidneys. Various other
toxins are associated with A. versicolor,such
as aspercolorin, averufin, cyclopiazonic acid, and versicolorin.
Additionally, the volatile organic compound (VOC) "geosmin" is
generated by the action of this mold. Often an irritant to
mucus membranes of humans and pets, geosmin has a musty, earthy
odor.

Basidiomycetes
Taxonomic designation for fungi of the subdivision "Basidiomycotina",
which includes mushrooms and puffballs. They produce spores that are formed
on the outside of a special cell, called the "basidium".

basidiospore
An exogenous sexual spore (meiospore) borne on a basidium. Or, a spore from
a basidiomycete (a member of Basidiomycetes). Many varieties are reported
to be allergenic.

BipolarisA fungus with large spores that could be expected to be
deposited in the upper respiratory tract. This fungus can produce
the mycotoxin - sterigmatocystin, which has been shown to produce
liver and kidney damage when ingested by laboratory animals.

BlastomycesHuman pathogen. The fungus is commonly found in soil. It
is a dimorphic fungus that has filamentous fungus when grown
at 25 degrees C. and a yeast form at 37 degrees C.

BotrytisAw 0.93. Conidia dimensions: 7-14 x 5-9 microns. It is
parasitic on plants and soft fruits. Found in soil and on house
plants and vegetables, it is also known as "gray mold".
It causes leaf rot on grapes, strawberries, lettuce, etc. It
is a well-known allergen, producing asthma type symptoms in
greenhouse workers and the symptoms of "wine grower's
lung".

CandidaPart of the normal flora of mouth and other mucous membranes
in the body. Thrush and other diseases caused by Candida
albicans usually occur after prolonged treatment with antibiotics
or steroids. The environment is not a likely source of exposure
for this fungus. Cells from the organism are usually not airborne.
Reported to be allergenic.

CephalosporiumSee Acremonium

ChaetomiumLarge ascomycetous fungus producing perithecia. It is found
on a variety of substrates containing cellulose, including
paper and plant compost. It has been found on paper in sheetrock.
It can produce an Acremonium-like state on fungal media.
Varieties are considered allergenic and have been associated
with peritonitis, cutaneous lesions, and system mycosis.

Cladosporium fulvum(Fulvia fulva)
Conidia dimensions: 12-47 x 4-10 microns. It is found on the leaves of tomatoes.

Cladosporium (Hormodendrum)Aw 0.88; Aw 0.84. Most commonly identified outdoor fungus.
The outdoor numbers are reduced in the winter. The numbers
are often high in the summer. Often found indoors in numbers
less than outdoor numbers. It is a common allergen. Indoor Cladosporium sp.
may be different than the species identified outdoors. It is
commonly found on the surface of fiberglass duct liners in
the interior of supply ducts. A wide variety of plants are
food sources for this fungus. It is found on dead plants, woody
plants, food, straw, soil, paint, and textiles. Produces greater
than 10 antigens. Antigens in commercial extracts are of variable
quality and may degrade within weeks of preparation. Common
cause of extrinsic asthma (immediate-type hypersensitivity:
type I). Acute symptoms include skin lesions, eye ulceration,
mycosis (including onychomycosis, an infection of the nails
of the feet or hands) edema and bronchiospasms; chronic cases
may develop pulmonary emphysema.

Cladosporium sphaerospermumConidia dimensions: 3-4.5 microns. It is found as a
secondary invader of plants, food, soil, paint and textiles.

conidiumA thin-walled, asexual spore borne exogenously on an often
specialized hypha (conidiophore) and is deciduous at maturity.
(plural form: conidia.)

conidia, unidentifiedThese are mold spores that do not show morphological characteristics
that allow identification. Because there are tens of thousands
of types of fungi, many fall into the "other" or "unknown" category.
If they are present in significant numbers, additional measures
can be taken to identify them. When spore counts are listed
in the category: "Unidentified Conidia" their numbers
are considered "normal".

Cryptococcus neoformansA basidiomycetous encapsulated fungal organismfound
worldwide, mainly around pigeon roosts and soil contaminated
with decaying pigeon or chicken droppings. It is generally
accepted that the organism enters the host by the respiratory
route in the form of a dehydrated haploid yeast or as basidiospores.
Hematogenously spreading to extrapulmonary tissues, its predilection
for the brain means infected persons usually contract meningoencephalitis,
which can be fatal.

Cryptostroma corticaleConidia dimensions: 4-6.5 x 3.5-4 microns. Found on
the bark of maple and sycamore trees and on stored logs.

CurvulariaReported to be allergenic and has been associated with
allergic fungal sinusitis. It may cause corneal infections,
mycetoma, and infections in immune compromised hosts.

DictyosporiumA fungal genus of the classification group "Hyphomycetes".At
this time, there is no information available concerning Dictyosporium allergenicity
or toxicity, but as a member of the classification group "Dematiaceous
Hyphomycetes", it could potentially cause phaeohyphomycosis
(see phaeohyphomycosis).It is found in terrestrial and freshwater
habitats, and is a common saprobe of submerged lignocellulose
substances.The microscope reveals its spores to be multicellular
and tongue-shaped; with subconcentric cells.Colonies may appear dark brown, green-black,
or black.

DreschleraConidia dimensions: 40-120 x 17-28 microns. Found on grasses,
grains and decaying food. It can occasionally cause a corneal
infection of the eye.

EpicoccumConidia dimensions: 15-25 microns. A common allergen. It
is found in plants, soil, grains, textiles and paper products.

fungus
Neither animals nor plants, these saprophytic and parasitic spore-producing
organisms rate a taxonomic kingdom of their own. Fungi include molds, rusts,
mildews, smuts, mushrooms, puffballs, and yeasts. It is estimated that more
than 1.5 million species of fungi exist.

Fusarium solaniAw 0.90. Macroconidia dimensions: 27-52 x 4.4-6.8;
Microcondia dimensions: 8-16 x 2-4 microns. Found in plants
and soils. Can produce trichothecene toxins that may be associated
with disease in humans and animals.

FusariumAw 0.90. A common soil fungus. It is found on a wide range
of plants. It is often found in humidifiers. Several species
in this genus can produce potent trichothecene toxins. The
trichothecene (scirpene) toxin targets the following systems:
circulatory, alimentary, skin, and nervous. Produces vomitoxin
on grains during unusually damp growing conditions. Symptoms
may occur either through ingestion of contaminated grains or
possibly inhalation of spores. The genera can produce hemorrhagic
syndrome in humans (alimentary toxic aleukia). This is characterized
by nausea, vomiting, diarrhea, dermatitis, and extensive internal
bleeding. Reported to be allergenic. Frequently involved in
eye, skin, and nail infections.

GeotrichumAw 0.90. Conidia dimensions: 6-12 x 3-6 microns. Aw 0.90.
A common contaminant of grains, fruits, dairy products, paper,
textiles, soil, and water; often present as part of the normal
human flora. The species Geotrichum candidum can cause
a secondary infection (geotrichosis) in association with tuberculosis.
This rare disease can cause lesions of the skin, bronchi, mouth,
lung, and intestine.

GliocladiumA fungus that is structurally similar to Penicillium sp.
It is reported to be allergenic.

HelicomycesA mitosporic mold often encountered on decaying plant matter.
The genus name prefix "helico" is derived from the
shape of the mold's microscopic structure; certain filaments
(sometimes the conidia) curve into a helical path.

Reported effects upon human health in the indoor environment are not available
at this time.

Scientists have shown the interaction of Helicomyces roseus with
nitrogen-fixing bacteria to be a vital component of an effective soil enriching
system (where sugar cane litter is the decomposition target). Helicomyces
lilliputeus has long been known as an important sewage treatment systems
decomposer, so it is not unexpected that other members of this genus have
been observed living on wood submerged in water.

HelminthosporiumReported to be allergenic.

HistoplasmaA fungus that has filamentous growth at 25 degrees C. and
yeast growth at 37 degrees C. It is reported to be a human
pathogen. It may be associated with birds.

HumiculaGrows on products with a high cellulose
content. These fungi are also found in soil and on plant debris.

hyaline myceliaMycelia that are transparent, translucent, or colorless.
If no reproductive structures are present, identification is
difficult. Often associated with allergic symptoms.

hypha (plural form: hyphae)
One of the tubular, filamentous, branching structures of a fungus (including
mold) that develop from germinated spores. A hypha is often divided into
sections (of several cells in linear succession) by cross walls called "septa" that
usually have perforations through which cytoplasm flows. It is the main means
of growth for fungi, and a collective or mass of hyphae is referred to as “mycelium”.

Memnoniella
A cellulolytic fungus that is very closely related to Stachybotrys sp.
Both fungi have a worldwide distribution and are often found together and are
commonly found in soil. Recent studies on mycotoxins revealed that Memnoniella
echinata can have a toxicity similar to that of some isolates of Stachybotrys
chartarum. Both produce varying amounts of simple trichothecenes. Thus,
it is suggested that Memnoniella sp. should also be considered potentially
dangerous in indoor air. The major difference between the two fungi is that
the conidia of Memnoniella sp. are in long persistent chains while those
of Stachybotrys are aggregated in slimy heads. Also the aerodynamic
diameter of Memnoniella sp. conidia is smaller and it would be expected
to have an even greater potential to penetrate deep into lungs than the conidia
of Stachybotrys sp.

MicrosporumCauses ringworm in humans.

mold
Molds are a group of organisms that belong to the taxonomic kingdom of Fungi.
There are over 20,000 species of mold. Molds reproduce by making spores.
Mold spores waft through the indoor and outdoor air continually. When mold
spores land on a damp spot indoors, they may begin growing and digesting
whatever they are growing on. Molds can grow on virtually any organic substance,
as long as moisture and oxygen are present.

MoniliaReported to be allergenic. This fungus produces soft rot
of tree fruits. Other members produce a red bread mold. It
is infrequently involved in corneal eye infections.

MucorOften found in soil, dead plant material, horse dung, fruits
and fruit juice. It is also found in leather, meat, dairy products,
animal hair, and jute. A Zygomycetes fungus that may be allergenic
(skin and bronchial tests). This organism and other Zygomycetes
will grow rapidly on most fungal media. May cause mucorosis
in immune compromised individuals. The sites of infection are
the lung, nasal sinus, brain, eye, and skin. Infection may
have multiple sites.

Mycelium (plural
form: mycelia)
A mass of interwoven hyphae (a hypha is a filamentous part of a fungus that
usually has several cells in linear succession with dividing walls in between)
that is often submerged in soil or organic matter or the tissues of a host.

MyxomycetesA taxonomic designation for fungi that are included in
the category of "slime molds". They're occasionally
found indoors, but mainly reside in forested regions on decaying
logs, stumps, and dead leaves. Myxomycetes display characteristics
of fungi and protozoans. In favorable (wet) conditions
they exhibit motile, amoeba-like cells, usually bounded only
by a plasma membrane, that are variable in size and form. During
dry spells, they form a resting body (sclerotium) with dry,
airborne spores. These fungi are not known to produce toxins,
but can cause hay fever and asthma.

NigrosporaCommonly found in warm climates, this mold may be responsible
for allergic reactions such as hay fever and asthma. It is
found on decaying plant material and in the soil. It is not
often found indoors.

OidiumThe asexual phase of Erysiphe sp. It is a plant
pathogen causing powdery mildews. It is very common on the
leaves stems, and flowers of plants. The health effects and
allergenicity have not been studied. It does not grow on non-living
surfaces such as wood or drywall.

PaecilomycesCommonly found in soil and dust; less frequently in air. P.
variotii can cause paecilomycosis. Linked to wood-trimmer’s
disease and humidifier associated illnesses. They are reported
to allergenic. Some members of this genus are reported to cause
pneumonia. It may produce arsine gas if growing on arsenic
substrate. This can occur on wallpapers covered with Paris
green.

Papulospora
These fungi are found in soil, textiles, decaying plants, manure, and paper.

PenicilliumAw 0.78 - 0.88. A wide number of organisms have been placed
in this genus. Identification to species is difficult. Often
found in aerosol samples. Commonly found in soil, food, cellulose
and grains. It is also found in paint and compost piles. It
may cause hypersensitivity pneumonitis, allergic alveolitis
in susceptible individuals. It is reported to be allergenic
(skin). It is commonly found in carpet, wallpaper, and in interior
fiberglass duct insulation. Some species can produce mycotoxins.
Common cause of extrinsic asthma (immediate-type hypersensitivity:
type I). Acute symptoms include edema and bronchiospasms; chronic
cases may develop pulmonary emphysema. It may also cause headaches,
vomiting, and diarrhea.

PericoniaFound in soil, blackened and dead herbaceous stems, leaf
spots, grasses, rushes, and sedges. Almost always associated
with other fungi. Rarely found growing indoors. Reportedly
associated with a rare case of mycotic keratitis.

peritheciumA fruiting body of a fungus in which some types of spores
(including ascospores) are produced. (plural form: perithecia)

PeronosporaThese species are plant pathogens and the genus is one
that causes downy mildews. Peronospora is very common
and is an obligate parasite (obligate parasites cannot grow
on non living environmental surfaces) found on leaves, stems,
flowers, and fruits of living higher plants. Peronospora sp.
may be identified in air on spore trap samples since spores
have a distinctive morphology. The spores may also be seen
in dust as part of the normal influx of outdoor microbial particles.
As of this writing, allergenicity has not been studied and
no information is available regarding health effects or toxicity.

phaeohyphomycosis
A hyphomycosis (infection by a mold of the taxonomic designation "Hyphomycetes")
in which the infiltrating microbes are usually of the mold family "Dematiaceae",
and are characterized by the coloring of their mycelium; the prefix "phaeo" means "dusky-brown".
Various forms of the disease involve different areas of the body, such as the
skin or respiratory tract. Intrusion of the mold in the eye, brain, bone, or
subcutaneous tissue typically occurs as a result of trauma to the affected
area.

PhomaA common indoor air allergen that can cause hay fever,
asthma, and a type of hypersensitivity pneumonitis commonly
called "shower curtain disease" (shower surfaces
being among those frequented by this fungal organism). Phoma infections
in humans also have been reported; usually affecting the immunocompromised,
they include mycotic keratitis (fungal infection of the cornea),
skin infections, and phaeohyphomycosis (see phaeohyphomycosis).

For a positive identification of this genus, the specimen must contain
the pycnidia (a round to pear-shaped fruiting structure containing conidia)
to confirm the presence of simple phialides (a cell from which conidia
are extruded). A cultured sample would provide these components. Colonies
are rapid growing, appear powdery to velvety, and exhibit many different
colors. This mold is known to grow on butter, rice, potatoes, paint (sometimes
seen as pink and purple spots on painted walls), cement, rubber, wood,
paper, and under linoleum. In nature, the species are found in soil, manure,
on fruit, dead plants, and as parasites on live plants.

Researchers have discovered that when Phoma macrostoma is sprinkled
onto the soil in areas with no preexisting weeds, it acts as an earth-friendly
herbicide, inhibiting the ability of many broadleaf plants (including dandelions)
to produce chlorophyll; the young broadleaf plants turn white and die while
grass seems to be unaffected.

PithomycesA native of mostly tropical environments, it commonly grows
on dead plants, soil, wood, and especially the dead leaves
and grasses of livestock fodder. Pithomyces chartarum produces
sporidesmin (a piperazinedione), a mycotoxin known to cause
animal liver damage, and it causes facial eczema in cattle,
sheep, and goats. For humans, it is considered a possible allergen,
and a potential infectious agent in immunocompromised patients.

Not known to be prolific indoors, this mold can sometimes be found on paper.
It exhibits distinctive multi-celled brown conidia.

RhizomucorThe Zygomycetous fungus is reported to be allergenic. It
may cause mucorosis in immune compromised individuals. It occupies
a biological niche similar to Mucor sp. It is often
linked to occupational allergy. May cause mucorosis in immune
compromised individuals. The sites of infection are the lung,
nasal sinus, brain, eye, and skin. Infection may have multiple
sites.

RhizopusThe Zygomycetous fungus is reported to be allergenic. It
may cause mucorosis in immune compromised individuals. It occupies
a biological niche similar to Mucor sp. It is often
linked to occupational allergy. May cause mucorosis in immune
compromised individuals. The sites of infection are the lung,
nasal sinus, brain, eye, and skin. Infection may have multiple
sites.

RhodotorulaA reddish yeast typically found in moist environments such
as carpeting, cooling coils, and drain pans. In some countries
it is the most common yeast genus identified in indoor air.
This yeast has been reported to be allergenic. Positive skin
tests have been reported. It has colonized terminally ill patients.

rusts (and smuts)
These fungi are associated with plant diseases. In the classification scheme
of the fungi, the smuts have much in common with the rusts, and they are
frequently discussed together. Both groups produce wind-borne, resistant
teliospores that serve as the basis for their classification and their means
of spread. Rusts usually attack vegetative regions (i.e., leaves and stems)
of plants; smuts usually are associated with the reproductive structures
(seeds). They can cause hay fever and asthma.

SaccharomycesReported to be allergenic. Baker's yeast.

ScopulariopsisIt may produce arsine gas if growing on arsenic substrate.
This can occur on wallpapers covered with Paris green. It has
been found growing on a wide variety of materials including
house dust. It is associated with type III allergy.

SepedoniumMost easily recognized by the spores, which are colorless
to yellow, spiny, round, 1-celled, and produced singly at the
ends of short filaments. Sometimes phialides of the Acremonium or Gabarnaudia type
may also occur. A few species of Mortierella, as well
as the human pathogen Histoplasma capsulatum, produce
spores resembling those of Sepedonium. Isolated from
soil, but most commonly parasitized mushrooms.

SpegazziniaThis mitosporic fungus (spores develop by means of
asexual cell division) is included in the classification group "Hyphomycetes".
At this time, no information is available concerning Spegazzinia allergenicity
or toxicity. Spegazzinia spores can be identified in
air samples by their distinctive structure, and have the potential
to produce a colony within seven to ten days. Colonies are
considered relatively slow growing, and are brownish-black
to black in color. This saprobe (deriving its nourishment from
nonliving or decaying organic matter) is most commonly found
in warm-temperate to tropical areas in soil and on dead leaves,
stems, trees, and other various kinds of plant debris.

spore
The means by which molds reproduce. Spores are microscopic (2-100 micrometers)
and various shapes. Distribution can be accomplished by a breeze, water droplet,
or a person or animal passing by. They can even be discharged by the mold
(usually under moist conditions or high humidity).

SporobolomycesReported to be allergenic.

SporoschismaA mitosporic fungal genus of the classification group "Hyphomycetes".At
this time, no information is available concerning Sporoschisma allergenicity
or toxicity.It is
known to exist on wood and stems, and these can be submerged
in fresh water.Microscopic features include quadriseptate spores, originating
in an enclosed membrane.

SporothrixThe species Sporothrix schenckii can cause sporotrichosis,
but usually only in individuals that are immune compromised.
Sporotrichosis is a chronic fungal infection that results when
the mold enters the body where the skin is damaged or via the
lungs. If it reaches the bloodstream, it can affect many other
parts of the body.

SporotrichumReported to be allergenic. Additionally, Sporotrichum
pruinosum has been observed in the respiratory secretions
of some human patients, indicating a possible ability to colonize
the bronchopulmonary pathways. This genus does not cause sporotrichosis
(see alsoSporothrix, for there is some taxonomic
confusion between these two genera).

Rarely found in cooler regions, Sporotrichum is prevalent in warm-temperate
and tropical zones, and grows (rapidly) on soils, decaying plant matter,
wet or rotting wood, grasses, and landscaping mulch. Colonies may appear
white, rosy-beige, or orange, and have a velvety to granular texture.

StachybotrysAw - 0.94 , optimum Aw ->0.98. Several strains of this
mold (S. atra, S. chartarum, and S. alternans are
synonymous) may produce macrocyclic trichothecenes (one of which
is Satratoxin H) that are poisonous by inhalation. These mycotoxins,
when present, are primarily associated with the mold's spores.

Individuals with chronic exposure to Stachybotrys's toxins reported
cold and flu symptoms, sore throats, diarrhea, headaches, fatigue, dermatitis,
hair loss, general malaise, and psychological depression. For infants, the
toxins create a vulnerability to a serious condition called pulmonary hemosiderosis
(bleeding in the lungs) where severe bleeding can result in coughing blood
or nosebleeds, and low grade bleeding can cause chronic coughs and congestion
with anemia. People who unknowingly handled material contaminated with this
mold described symptoms of cough, rhinitis, burning sensations of the mouth
and nasal passages, and cutaneous irritation at the point of contact, especially
in areas of abundant perspiration. The toxins produced by this mold will suppress
the immune system, affecting the lymphoid tissue and the bone marrow. Animals
injected with macrocyclic trichothecenes exhibited the following symptoms:
necrosis and hemorrhage within the brain, thymus, spleen, intestines, lung,
heart, lymph nodes, liver, and kidneys.

This is a dark-colored fungus that grows on building materials with a high
cellulose content and a low nitrogen content. It is slow growing when compared
to other common molds, and may not appear to compete well in their presence.
Yet, when moisture levels are high for prolonged periods, Stachybotrys may
gradually become the dominating genus (possibly because of its yield of mycotoxins,
which are believed to be directed against other molds and bacteria). This organism
is usually difficult to find in indoor air samples unless it is physically
disturbed, but when it does appear it is an alert to find the source, as it
will likely be found growing in abundance. Its spores--which can be found in
a gelatinous mass--will die readily after release, but are still allergenic
and can be toxigenic. Areas with a relative humidity above 55%, and are subject
to temperature fluctuations, are ideal for toxin production.

StemphyliumThis genus is included in the taxonomic designation "Hyphomycetes".
It is a known allergen, causing Type I allergies (examples:
hay fever, asthma). Phaeohyphomycotic sinusitis has been reported
in connection with this mold. (See phaeohyphomycosis.)

Existing mainly in the temperate northern hemisphere, it can be found
in soil, moist wood or cellulose materials, on decomposing plants, and
as pathogens on living plants (leaf spots are one example). Colonies grow
rapidly, and appear velvety to cottony in texture; coloring is light brown
or olive green to black. Though it is rare to find indoor colonization,
it has been found in dust that is transferred in from outside, including
dust on air filters.

Taeniolella
(Phonetic Pronunciation: Tay-knee-ol’-el-luh) This genus of the classification
group "Dematiaceous Hyphomycetes" has been isolated from human cutaneous
and subcutaneous lesions, making it a possible etiological agent of phaeohyphomycosis
(see phaeohyphomycosis). Studies of its allergenicity and toxicity are
not known at this time. Taeniolella lacks a known sexual state (placing
it in the "Fungi Imperfecti" category) and is known to reproduce
asexually by the process of mitosis. In temperate North America, this weak
saprobe’s natural habitat commonly includes dead branches, wood, and senescent
leaves. Indoors, they are sometimes found on lumber, other forms of wood, and
plants. Taeniolella may be identified from tape lift, bulk, or airborne
spore samples.

TorulaFound outdoors in air, soil, on dead vegetation, wood,
and grasses. Also found indoors on cellulosic materials. Reported
to be allergenic and may cause hay fever and asthma.

Trichocladium
This is a widespread mitosporic (lacking a sexual state) fungus of the classification
group "Hyphomycetes". There is little information regarding toxicity
or allergenicity, but it is known to rarely be the causative agent for human
keratitis (infection of the cornea).

Various species of this genus may be identified from indoor sampling (one
species in particular, Trichocladium uniseptatum, is found regularly
on indoor environmental surfaces, especially wood). Outdoors, it
is found on dead wood, stems or twigs, tubers of various plants, pine
needles, other plant debris, and in soils. It is notable that
this microbe has been associated with black root rot, as an
aggressive plant pathogen.

TrichodermaIt is commonly found in soil, dead trees, pine needles,
paper, and unglazed ceramics. It often will grow on other fungi.
It produces antibiotics that are toxic to humans. It has been
reported to be allergenic. It readily degrades cellulose.

TrichophytonCan cause ringworm, athlete's foot, jock itch, and other
infections of the skin, nail, beard and scalp. Reported to
be allergenic. Found on soil and skin.

TrichotheciumAw 0.90. Conidia dimensions: 12-23 x 8-10 microns. Found
in decomposing vegetation, soil, corn seeds, and in flour.
The species Trichothecium roseum can produce a trichothecene
toxin that may be associated with disease in humans and other
animals. Reported to be allergenic.

TritirachiumReported to be allergenic.

UlocladiumAw 0.89. This mold is reported to be a major allergen,
capable of causing hay fever and asthma. It is also known to
rarely cause subcutaneous infections.The
University of Adelaide, Australia, categorizes this microbe
in the classification group “Dematiaceous Hyphomycetes”, which
includes it as a possible causative agent of phaeohyphomycosis
(see phaeohyphomycosis).

Widely distributed
in nature and considered a saprobe (weak parasite), some of its growth
sites are soil, grasses, dead or dying plants (mainly herbaceous vegetation),
manure, and compost. In interior environments it has been found on paper,
painted surfaces, gypsum board, textiles, jute, straw materials, carpets,
cellulose building materials (including wood), and in dust and air samples.
Colonies are moderately fast growing, usually appearing olive-brown (or
rusty-brown) to black (or grayish), with a texture that is granular to
velvety.

yeastVarious yeasts are commonly identified on air samples.
Some yeasts are reported to be allergenic. They may cause problems
if a person has had previous exposure and developed a hypersensitivity.
Yeasts may be allergenic to susceptible individuals when present
in sufficient concentrations.

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"Aw" refers
to the water
activity measurement, where Aw is equal to the relative humidity
of the air surrounding the sample when the air and the sample are at
equilibrium (in an enclosed space).